Drier agitator



May 16, 1-933. A. F. WENDLER DRIER AGITATOH Filed Oct. 19, 1925 2 Sheets-Sheet l Af WENDLEE.

J 6310 fn/qg A. F. WENDLER DRIER AGITA'IOR May 16, 1933.

Filed Oct. 19, 1925 2 Sheets-$heet 2 2% WWW 7mm Patented May 16, 1933 PATENT I OFFICE ADOLPH r. WENDLER, or BUFF LG, Nnwyonmnssreivon TO THE NATIONAL ANILINE AND CHEMICAL 00., INC., OF. NEW YORK, N. A CORPORATION or new Yonx nnrnn AGITATOR Application filed October 19,1925. Serial naeaas This invention relates to agitators and in particular to agitators for horizontal'driers for drying wet or moist material by evaporation of liquid therefrom.

Agitators, as commonly constructed for use with driers, are of two types, one, a continuous helix, commonly designated as spiral, and the other, a horizontal paddle. With each form it is found that the-material becomes packed in spots and'at times the consequent resistance becomes great enough to stall the machine or cause breakage, requiring stoppage of the drying operation. Furthermore, while the horizontal paddlespro- 0 vide a mixing and tumbling'ofthe material,

a longperiod for unloading is necessary. On the other hand, while the helical type" accelerates unloading, the mixing and tumbling action is virtually absent, and the extended agitator periphery adjacent the drier shell and the allowance requiredfor expansion does not permit adjustment to givea close contact with the drier shell and effec'tan effi- 5 cient drying action.

By the present invention substantially even distribution of the material is maintained;

and there is combined the mixi'ng and tumbling operation of the paddletype with the endwise thrust and axialmovement of the material which the helical type affords. Ad justability is at the same time provided so that eflicient drying action is obtained.

A suitable apparatus embodying't'he inven 0 tion comprises a plurality ofmaterial contact members such as blades or paddlesmounted in staggered relation about a shaft and in part or wholly helically formedto give axial or endwise movement to'the material. For each paddle pitched in one direction, there is preferably provided another paddlepitched in the opposite direction so that the endwise shift of material in. one axial direction is balanced by an endwise shift in the contrary axial direction. The paddles individually are in short sections, preferably being short sectionsof a helix. The pitch of the blades is such that,in rotating, the forward portion of a blade is advanced a relatively small distance ahead of the rear portion; i. e. a projection of a blade upon a plane perpendicular to the axis of rotation subtends a relatively small arc, and consequently the blades can be given an adjustable mounting to bring them into as close a contact with the shell as inequalities thereinwillpermit. Changes due to expansion can also'be compensated by the adjustment so provided. v,

The relatively short paddles in staggered position aboutthe shaft give an interrupted helical formation, so that there is no extended endwise travel of the material, and that which is so shifted by one blade is deposited in the path of arr-adjacent one. Accordingly the causes for packing or clogging are absent.

The forward face of the blades or paddles which contacts or bears against the material may extend normally to the shaft surface, but under such conditions there is a tendency for the material to ball up or roll into a pill formation. This action is corrected by pro viding the blades witha forwardly extending portionwhich is inclined rearwardlv with respectto thedirection of'rotation. This inclined portion of the blades shears the mate rial away from the casing and radially inward toward the shaft. l

The shearing action not only maintains the material in a friable condition, but drying is hastened, particularly when a heated hollow shaft is used. Moreover, resistance to the agitator-rotation, which arises in connection with normally set paddles due to the material being-forced against the shell, is largely obviated; and the fact that the material is sheared rather than pushed considerably lessens the power consumption and wear on the parts, allows overloading without danger of breakage, and lessens dusting. In the accompanying drawings, Fig. 1 is a longitudinal section of a drier showing an agitator with the blades or paddles partially pitched along helical lines;

Fig. 2 is a cross-section of Fig. 1 on the line IIII;

Figs. 3 and 4 are details showing the bracket construction;

Fig. 5 is a partial section of the hollow shaft;

Fig. 6 is a side view of the dipper shown in Fig. 5;

Figs. 7 and 8 are views of the paddle shown in Fig. 1;

Fig. 9 is a longitudinal section similar to Fig. 1 but disclosing sets of paddles alternating in pitch;

Fig. 10 is a partial cross-section of Fig. 9;

Fig. 11 is an elevation of the paddle shown in Fig. 10; and

Fig. 12 is a cross-section of another embodiment showing a modified form of arm and paddle, the paddles of each set alternating in pitch.

The embodiment, illustrated in Figs. 1 and 2, is one in which the blades are in part pitched about the shaft surface. A cylindrical shell or casing 1 has a drying chamber surrounded by a jacket 2 so that steam or other heating medium may be circulated within it. Heads 3 and 4 close each end of the casing and bearings 5 and 6 are carried by the heads. Within the bearings rotate trunnions 7 and 8, and connecting the trunnions is an extra heavy pipe shaft 9 which has a shrink tight fit in the trunnions and is further secured to them by patch bolts 10 and welding. Each trunnion has an axial passage 11 through it for the entrance and exit of a heating medium; and, when steam or other condensable medium is used, the outlet passage is preferably provided with a pipe 12 threaded in it, which pipe carries a dipper 13. The dipper has a lower surface 14 contiguous to the interior surface of the pipe shaft, and water of condensation is picked up and so removed from the hollow shaft by the dipper as it rotates with the shaft.

"Vapors given off during the drying are withdrawn in any well known manner, and the dried material is removed by opening the normally closed discharge ports 50.

Encircling the revoluble shaft are a plurality of brackets 15, each one having arms 16 extendingradially and four arms being shown to each bracket. The brackets are in half sections bolted together and are held from rotation on the shaft by keys 17 In each arm is a slot 18. Connecting an arm of one bracket to an arm of an adjacent bracket is a paddle 20, which has lugs 21 ex tending from it at each end. Bolts 22 secure thelugs to the arms, the bolts passing through the slots 18 in the arms, and a pair of bolts are provided for each lug to hold it securely and overcome any tendency to vibration. The slot permits radial adjustment of the blade. Two paddles or blades, lying diametrically opposite and pitched to move material in the same axial direction, are shown connecting each pair of brackets and constitute a set. There are therefore two sets of blades connected to each bracket, with the exception of the end brackets, one set being offset and axially displaced from the other. Obviously a set may comprise more than two blades, and the offset be any desired angle.

The paddle construction, illustrated in connection with this embodiment, is one of cast steel having a forwardly extending, rearwardly inclined portion 23 and a cutting edge 24 to shear through the material; To

give stiffness, the middle section 25 of the blade is made wider, and a rib 26 at the rear of the blade further strengthens it.

Some of the paddles are helically bent and others are parallel to the shaft axis. As shown in Fig. 1, on each side of a parallel mounted paddle is secured a helically bent paddle pitched to throw, material toward it. The parallel paddle in view of its enlarged middle section has a tendency to return material toward the helical paddles; and as the material is sheared through and lifted'by the parallel paddles, an axial movement of the material as a whole is neutralized by the re,- verse pitch of the helical paddles. The staggered arrangement gives a freedom of flow so that there is no packing or clogging.

The, angle subtended by a projection of pitched blade upon a plane perpendicular to the shaft axis is preferablywithin a range from 15 to 45 to permit its ready-adjustment to the shell surface and to give allowance for expansion. Each paddle, therefore, is in effect a short section of a helix. Accordingly the staggered relation places axially adj acent'paddles within wholly different segments or quarter cross sections.

Other embodimentsin which the axially adjacent paddles or blades are alternately pitched, individually or in multiple, are 3 shown in Figs. 9 to 12 inclusive. The casing shaft and bracket construction of Figs. 9 to 11, inclusive, is the same as in the preceding form, the difference lying in the paddles and their mounting. The paddle here illustrated consists. of a sheet metal blade portion 30 and extending lugs 31, 32; the end portions 33, 3 1 of the blade, carrying the lugs, are ina bent position so as to be parallel to the shaft axis, and the whole blade length is in a forwardly extended position, the blade inclining rearwardly with respect to the direction of rotation, preferably at an angle of about-30 from the normal. A cutting, edge 35 is given the outer or forward edge by beveling it-as shown, and the beveling is made to conform to the shell so as to bring the cutting edge in close proximity to the shell.

In the forms of the device shown in Figs. 9 to 12, the interposed parallel paddle is missing. Consequently material contractedv by one helical-blade is sheared axially or endlessens dusting. If instead of the axially adjacent blades being pitched in the opposite directions, a multiple of axially adjoining blades pitched in the same direction are followed'by a multiple of axially adjoining blades pitched in the opposite direction, as shown in Fig. 12, the material is pushed a greater axial distance before its axial direction is reversed.

The paddles illustrated in Figs. 9 to 11 are of plate steel, as this material is satisfactory, relatively inexpensive, and the blades can be readily constructed; the helical form gives the requisite stiffness to withstand distortion. For simplicity, ease of installation, and need for but one type,'brackets with nor mally extending arms and faces parallel to the axial plane are preferred. But other forms of arms and other types of paddle are feasible. As an illustration, Fig. 12 shows an arm 40 having an extension 41which is bent from the normal to give the desired rake and is skewed from the axial plane at the desired pitch. For use with such an arm, a blade 42 is bolted to the extensions 41, and the extending lugs from the blade are omit ted. A stiffening rib 43 is shown in the back of the blade and the blade is further shown as extending on either side beyond the bracket arms. 7

Whereas the pairs of blades of each set shown in Figures 1 and 9 are pitched to move material in the same axial direction, they may be oppositely pitched, as shown in Figure 12; and moreover, instead of those helical blades which lie in one segment of the axis being oppositely pitched with respect to each other as shown in Figure 1, they may be all pitched in the same direction, as shown in Figure 9. Obviously the blades lying in the same segment of the axis in the embodiment of Figure 9 may be also reversed with respect to each other, as are the helical blades shown in Figure 1.

The disclosed embodiments illustrate the mounting of the paddles on the shaft with adjacent sets of blades using a bracket in common, but different arms to stagger one set with relation to the next. Evidently independent brackets for each set can be used, the paddles may be overlapped and the staggered relation may be altered or partially omitted. Moreover, while the disclosure is directed to adjacent sets of paddles having a reverse pitch, it is obvious that paddles may be arranged in multiple having the same directional pitch with or without the staggered conformation, and similar arrangement of multiple paddles pitched in the opposite direction, equal in number when no movement of the material body as a whole in one directionor the other is desired; with such an arrangemenhit is desirable, that multiple blades pitched in onev direction be followed in rotation by multiple paddles pitched in the contrary direction. However, as the constructions disclosed give satisfactory drying and operating results, they are preferred in view of the simplicity and ease of erection.

Where in the claims a blade is referred to as subtending an arc ranging from 15 to 45, it is to be understood that'a projection of the blade upon aplane perpendicular to the axis of rotation of the blade will subtend an arc of rotation ranging from 15 to 45.

I claim:

1. In an apparatus for drying wet or moist material by evaporation of liquid therefrom,

and having in combination'a casing and an a plurality of setsof paddles mounted along said shaft and having a helical pitch, the length of the paddles constituting the sets being such as to extend through a segment not substantially more. than 45, alternate sets of paddles having reversed helical directions, and each of said paddles being adapted to cooperate with a wall of said casing.

2. In an apparatusfor drying wet or moist materialby evaporation of liquid therefrom, and having in combination a horizontal, stationary, cylindrical casing and an agitator adapted to cooperate therewith, the improvement which comprises a revoluble agitator shaft axially disposed within said casing, and a plurality of sets of paddles mounted along said shaft and having a helical pitch, alternate sets of paddles having reversed helical directions, and said paddles having a forwardly extending portion inclined from the normal to the shaft axis, and being disposed adjacent the inner wall of the casing whereby the paddles cooperate with said wall in shearing relation.

3. In an apparatus for drying wet or moist material by evaporation of liquid therefrom,

and having in combination a horizontal, stationary casing and an agitator adapted to cooperate therewith, the improvement which comprises a horizontal, revoluble, agitator shaft axially disposed within said casing, arms extending radially from said shaft, alternate axially disposed arms lying in one axial plane and intermediate axially disposed arms lying in an axial plane in angular relation to the first named plane, the angle between said planes ranging from 15 to 45, and material-contact members connecting adjacent arms, the length of said material-contact members being such as to extend through a segment of not substantially more than 45,

said members being positioned to cooperate with a wall of said casing, and the axially adjacent ends of axially adjacent members being staggered circumferentially.

4. In an apparatus for drying wet or moist material by evaporation of liquid therefrom, and having in combination a cylindrical casing and an agitator adapted to cooperate therewith, the improvement which comprises a revoluble agitator shaft axially disposed Within said casing, a plurality of sets of helical blades of relatively short section connected to said shaft, alternate sets of blades having reversed helical directions, and said blades subtending an arc ranging from 15 to 45 and being inclined rearwardly from a normal to the shaft surface.

5. In an apparatus for drying wet or moist material by evaporation of liquid therefrom, and having in combination a stationary, horizontal, cylindrical casing and a revoluble agitator adapted to cooperate therewith, the improvement which comprises a revoluble, horizontal, agitator shaft axially disposed within said casing, arms extending from said shaft, and blades of helical conformation and of relatively short section adjustably secured to said arms by means of lugs, said blades being inclined rearwardly from a normal to the shaft surface and beveled to give a forward cutting edge.

6. In an apparatus for drying wet or moist material by evaporation of liquid therefrom, and having in combination a heated casing and an agitator adapted to cooperate therewith, the improvement which comprises an agitator having means for moving material in a rotary direction while in contact with the inner wall of said casing, means for shearing said material from contact with said wall, and means for shifting said material back and forth in axial directions while in contact with said wall.

7. In an apparatus for drying wet or moist material by evaporation of liquid therefrom, and having in combination a heated casing and an agitator adapted to cooperate therewith, the improvement which comprises an agitator shaft, means carried by said shaft for moving material in a rotary direction while in contact with the inner wall of said casing, means carried by said shaft for shifting said material in one axial direction while shearing it from contact with said wall, and means carried by said shaft for shifting said material in the opposite axial direction while shearing it from contact with said wall.

8. In an apparatus for drying wet or moist material by evaporation of liquid therefrom, and having in combination a horizontal cylindrical casing and an agitator adapted to cooperate therewith, the improvement which comprises a horizontal, revoluble agitator shaft axially disposed within said casing, a plurality of sets of arms extending radially from said shaft, each set being disposed ina separate plane perpendicular to the axis of the shaft, and a plurality of pairs of diametrically opposed blades mounted on the ends of said arms adjacent the inner wall of said casing, each of said blades being short, helical, and r'earwardly inclined, and subtending an arc ranging from 15 to 45.

9. In an apparatus for drying wet or moist material by evaporation of liquid therefrom, and having in combination a horizontal cylindrical casing and an agitator adapted to cooperate therewith, the improvement which comprises a horizontal, revoluble agitater shaft axially disposed within said casing, a plurality of sets of arms extending radially from said shaft, each set being disposed in a separate plane perpendicular to the axis of the shaft, and a plurality of relatively short, helical blades supported at the ends of said arms adjacent the inner wall of said casing and connecting the successive arms of a set alternately with arms of the adjacent sets, said blades subtending an arc ranging from 15 to 455 and being inclined rearwardly from a normal to the shaft surface.

10. In an apparatus for drying wet or moist material by evaporation of liquid therefrom,and having in combination a horizontal cylindrical casing and an agitator adapted to cooperate'therewith, the improvement which comprises a horizontal, revoluble agitator shaft axially disposed within said casing, a plurality of sets of arms extending radially from said shaft, each set being disposed in a separate plane perpendicular to the axis of the shaft, and a plurality of short, helical, rearwardly inclined blades mounted in pairs on said arms in shearing relation with the inner wall of said casing, said blades connecting the successive arms of a set alternately with the arms of the adjacent sets, and the blades of a pair being diametrically opposed to each other and pitched to move material in opposite directions.

11. In an apparatus for drying wet or moist material by evaporation of liquid therefrom, and having in combination a casing and a revolvable agitator shaft within said casing and adapted to cooperate therewith, the improvement which comprises a plurality of pairs of paddles of relatively short, substantially equal length mounted diametrically opposite each other on said shaft, one of the paddles in a pair having a helical pitch in one direction, the other paddle in said pair having a helical pitch in the opposite direction, whereby said paddles shift the material in opposite direction, each of said paddles being equally distanced from said shaft and positioned to cooperate in shearing relation with the wall of said casing.

12. In an apparatus for drying wet or 7 said shaft and positioned to cooperate in P moist material by evaporation of liquid therefrom, and having in combination a casing and a revolvable agitator shaft within said casing and adapted to cooperate therewith,'the improvement which comprises a plurality of pairs of paddles of relatively short, substantially equal length mounted diametrically opposite each other on said shaft, the length of the paddles constituting the pairs being such as to extend'through a segment of not substantially more than 45, one of the paddles in a pair having a helical pitch in one direction, the other paddle in said pair having a helical pitch in the opposite direction whereby said paddles shift the material in opposite directions, each of said paddles being equally distanced from said shaft and positioned to cooperate in shearing relation with the wall of said casing.

13. In an apparatus for drying wet or moist material by evaporation of liquid therefrom, and having in combination a casing and a revolvable agitator shaft within said casing and adapted to cooperate there- I with, the improvement which comprises a plurality of pairs of paddles of relatively short, substantially equal length mounted diametrically opposite each other on said shaft, the length of the paddles constituting the pairs being such as to extend through a segment of not substantially more than 45, one of the paddles in a pair having a helical pitch in one direction, the other paddle in said pair having a helical pitch in the opposite direction, whereby said paddles shift the material in opposite directions, said paddles being mounted so that the working faces of the paddles are inclined rearwardly from the normal to the shaft axis, each of said paddles being equally distanced from shearing relation with the wall of said casing.

14. In an apparatus for drying wet or moist material by evaporation of liquid therefrom, and having in combination a horizontal casing and an agitator adapted to cooperate therewith, the improvement which comprises a horizontal revolvable agitator shaft axially disposed within said casing, arms extending from said shaft and disposed in spaced planes perpendicular to the axis of the shaft, blades having a helical pitch mounted on said arms and being rearwardly inclined from the normal to the shaft axis, and means for adjust-ing said blades toward and away from the inner wall of the casing so as to cooperate in shearing relation with the inner wall of said casing. V

15. In an apparatus for drying wet or moist material by evaporation of liquid therefrom, and having in combination a casing and an agitator cooperating therewith, the improvement which comprises an agitator shaft, a plurality of arms projecting from shaft and positioned to cooperate in shearing relation with the walls of said casing.

16. In an apparatus for drying wet or moist material by evaporation of liquid therefrom and having in combination a casing and an agitator cooperating therewith, the improvement which comprises an agitator shaft and a plurality of sets of paddles mounted along said shaft, at least two of the paddles of a set being disposed diametrically opposite to each other, being substantially of the same length, and being constructed and arranged to shift said material to be dried in opposite directions upon rotation of said shaft, and each of said paddles being equally distanced from said shaft and positioned to cooperate in shearing relation with the wall of said casing.

17. In an apparatus for drying wet or moist material by evaporation of liquid therefrom, and having in combination a horizontal cylindrical casing and an agitator adapted to cooperate therewith, the improvement which comprises a horizontal revolvable agitator shaft axially disposed within said casing, a lurality of sets of arms extending radially f i'om said shaft, each set being disosedin a separate plane perpendicular to the axis of the shaft, and a plurality of relatively short, helical blades supported at the ends of said arms adjacent the inner wall of said casing and connecting the successive arms of a set alternately with arms of the adjacent sets, said blades subtending an arc ranging from 15 to 45 and being inclined rearwardly from a normal to the shaft surface, and at least a pair of blades lying between and carried by adjacent sets of arms, the blades between adjacent sets of arms being pitched to move material in the same direction. i

18. In an apparatus for drying wet or moist material by evaporation of liquid therefrom, and having in combination a casing and an agitator cooperating therewith, the improvement which comprises an agitator shaft, a plurality of arms projecting from said shaft, a plurality bf sets of relatively short paddles carried by said arms and having a helical pitch, the paddles of a set being pitched to move material in the same direction; each paddle being supported by a pair of axially adjacentarms, the length of the paddles constituting the sets being substantially equal and such as to extend through a segment of not substantially more than 45, at least two adjacent sets of paddles having reversed helical directions, said paddles being mounted so that the Working faces'thereof are inclined rearwardly from the normal to the shaft axis, and each of said paddles being equally spaced from the shaft and positioned to cooperate in shearing relation with the Walls of said casing.

In testimony whereof I afiix my signature.

ADOLPH F. WENDLER. 

